Our long term objective is to understand, at the molecular level, how the plant hormone gibberellin (GA) regulates gene expression in rice, a representative cereal system. The specific objectives: 1 . To define the exact DNA sequence(s) in the regulatory regions of alpha-amylase genes required for the in vivo GA stimulation of gene expression. 2. To define the exact DNA sequence(s) In the regulatory regions of alpha-amylase genes required for the in vitro binding of the GA-dependent DNA binding (GA-DB) protein(s) in rice and relate this to results of in vivo experiments. 3. To test if the GA-dependent DNA binding protein(s) are transcription factor(s). 4. To purify and characterize the GA-dependent DNA binding protein(s). This is indicated if elements essential for GA action in vivo bind the protein dependent on GA in vitro. 5. To clone the gene(s) that codes for the GA-dependent DNA binding protein(s) in rice. 6. To look for mRNAs representing immediate response genes after GA induction.